Convertionproblem at "CausticAmoebas"

[J-i-P-i]

I have a shader here ( https://www.shadertoy.com/view/wl2SzR ) that cannot be converted. Compilation free of errors, but the sampling is incorrect.
My guess is it's because of these nested divisions:
in eq (): p.x / p.y
and then
O + = TONE / abs_f4 (to_float4_s (y-hs) -X);

The resulting image is limited to the lower left part, whereby only chaotic color pixels can be seen.

__DEVICE__ float4 abs_f4 (float4 a) {return (to_float4 (_fabs (a.x), _fabs (a.y), _ fabs (a.z), _ fabs (a.w)));}

// Tweak # 2 of sben's 'Flow of cells' (https://www.shadertoy.com/view/MlsGWX)
#define FIELD 10.0f
#define HEIGHT 0.7f
#define ITERATION 2.0f
#define TONE to_float4 (0.2f, 0.4f, 0.8f, 0)
#define SPEED 0.5f

__DEVICE__ float eq (float2 p, float t) {
   float x = _sinf (p.y-t + _cosf (t + p.x * 0.8f)) * _cosf (p.x-t);
   x * = _acosf (x);
   return - x * _fabs (x-0.05f) * p.x / p.y * 4.9f;
}

// ************************************************ ************************
  __KERNEL__ void ShaderToyKernel (__ CONSTANTREF__ ShaderToyParams * params, __TEXTURE2D__ iChannel0, __TEXTURE2D__ iChannel1, __TEXTURE2D__ iChannel2, __TEXTURE2D__ iChannel3, __WTERITE2 d) {
  DEFINE_KERNEL_ITERATORS_XY (x, y);
  if (x <params-> width && y <params-> height)
  {
    // -----------------------
     float2 U = to_float2 (x, y);
     float2 iResolution = to_float2 (params-> width, params-> height);
     float ratio = (float) params-> width / (float) params-> height;
     float itime = params-> itime;
     float4 O = to_float4_s (0.0f);
     // -----------------------

    // Functionality .......
    float4 X = O;
    float2 p = FIELD * (U / iResolution + 0.9f); // "iResolution / 0.15" test
    float t = itime * SPEED;
    float hs = FIELD * (HEIGHT + _cosf (t) * 1.9f);
    float x = eq (p, t);
    float y = p.y-x * 0.1f;
    
    for (float i = 1.0f; i <= ITERATION; i + = 1)
        p.x * = 1.5f,
        X = x + to_float4 (0, eq (p, t + i + 1.0f), eq (p, t + i + 2.0f), 0),
        x = X.z + = X.y,
        O + = TONE / abs_f4 (to_float4_s (y-hs) -X);

    _tex2DVec4Write (dst, x, y, O);
  }
}